PRTA (Prothena) Accumulated Depreciation: $-6.73 Mil (As of Jun. 2026)

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Dr. Charlie Tian is the founder and CEO of GuruFocus.com, a leading global investment research platform established in 2004. With a Ph.D. in physics, Dr. Tian transitioned from science to finance, applying a data-driven, disciplined approach to value investing.

PRTA Prothena Corp PLC PRTA
74 GF Score
Price $9.29
GF Value $12.96
Valuation Modestly Undervalued
! 2 Warning Signs
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What is Prothena Accumulated Depreciation?

Prothena PRTA +6.66% 74 Accumulated Depreciation is $-6.73 Mil as of Jun. 2026. GuruFocus rates PRTA with a GF Score™ of 74/100 and a GF Value™ of $12.96 (Modestly Undervalued). The stock has 2 warning signs investors should review.

Note: A negative number here means the assets are depreciated. When depricates more, the absolute value gets bigger.

Prothena's quarterly accumulated depreciation increased from Dec. 2025 ($-7.05 Mil) to Mar. 2026 ($-7.24 Mil) but then stayed the same from Mar. 2026 ($-7.24 Mil) to Jun. 2026 ($-6.73 Mil).

Prothena's annual accumulated depreciation increased from Dec. 2023 ($-7.42 Mil) to Dec. 2024 ($-8.31 Mil) but then stayed the same from Dec. 2024 ($-8.31 Mil) to Dec. 2025 ($-7.05 Mil).

Prothena Accumulated Depreciation Related Terms

Prothena Accumulated Depreciation Historical Data

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The historical data trend for Prothena's Accumulated Depreciation can be seen below:

* For Operating Data section: All numbers are indicated by the unit behind each term and all currency related amount are in USD.
* For other sections: All numbers are in millions except for per share data, ratio, and percentage. All currency related amount are indicated in the company's associated stock exchange currency.

Prothena Accumulated Depreciation Chart

Prothena Annual Data
Trend Dec16 Dec17 Dec18 Dec19 Dec20 Dec21 Dec22 Dec23 Dec24 Dec25
Accumulated Depreciation
Get a 7-Day Free Trial Premium Member Only Premium Member Only -10.46 -11.17 -7.42 -8.31 -7.05

Prothena Quarterly Data
Sep21 Dec21 Mar22 Jun22 Sep22 Dec22 Mar23 Jun23 Sep23 Dec23 Mar24 Jun24 Sep24 Dec24 Mar25 Jun25 Sep25 Dec25 Mar26 Jun26
Accumulated Depreciation Get a 7-Day Free Trial Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only Premium Member Only -7.40 -6.91 -7.05 -7.24 -6.73
PRTA
74GF Score
Prothena Corp PLC PRTA
Accumulated Depreciation is just one metric. See GF Score™, valuation, warning signs, and more.
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Prothena Accumulated Depreciation Calculation

The cumulative depreciation of an asset up to a single point in its life. Regardless of the method used to calculate it, the depreciation of an asset during a single period is added to the previous period's accumulated depreciation to get the current accumulated depreciation.

What does a Accumulated Depreciation of $-6.73 Mil mean?
Prothena (PRTA) has a Accumulated Depreciation of $-6.73 Mil as of Jun. 2026. Accumulated depreciation is a contra-asset item that accounts for the decline in value of long-term assets. View historical data on Prothena and its competitors.
Is Prothena's Accumulated Depreciation too high?
Prothena's current Accumulated Depreciation is $-6.73 Mil. Overall, Prothena has a GF Score™ of 74/100 and is considered Modestly Undervalued, reflecting its overall financial health beyond just this single metric.
How does Prothena's Accumulated Depreciation compare to KYTX and QTTB?
Prothena's Accumulated Depreciation of $-6.73 Mil can be compared against companies in the Biotechnology industry. See the competitive comparison table and distribution chart on this page for a detailed peer-by-peer breakdown.
What is a good Accumulated Depreciation for a Biotechnology company?
A good Accumulated Depreciation depends on the Biotechnology industry context. However, Accumulated Depreciation should not be evaluated in isolation — investors should consider it alongside profitability, growth, and financial strength metrics. Use the industry distribution chart on this page to see where any company falls relative to its peers.
What does a high Accumulated Depreciation mean?
A high Accumulated Depreciation can signal that a stock is expensive relative to its fundamentals. Accumulated depreciation is a contra-asset item that accounts for the decline in value of long-term assets. View historical data on Prothena and its competitors. Prothena's current Accumulated Depreciation is $-6.73 Mil. However, context matters — high-growth companies often justify higher valuations. Always evaluate alongside other metrics like GF Score™ and GF Value™.
Is Prothena stock overvalued right now?
Based on GuruFocus' analysis, Prothena (PRTA) is currently considered Modestly Undervalued. The stock's GF Value™ is $12.96, compared to a current price of $9.29 — trading 28.3% below its estimated fair value. The current Accumulated Depreciation is $-6.73 Mil. Prothena's overall GF Score™ is 74/100 with 2 warning signs to review. Investors should evaluate multiple metrics — including profitability, growth, and financial strength — before making a decision.
How is Accumulated Depreciation calculated?
Accumulated Depreciation is calculated from a company's financial statements. For Prothena (PRTA), the current Accumulated Depreciation is $-6.73 Mil as of Jun. 2026. GuruFocus calculates this using data sourced from SEC filings and annual reports. See the calculation section and 30-year financial data on this page for the full breakdown.

Is Prothena (PRTA) Overvalued in 2026?

Based on GuruFocus' analysis, Prothena stock appears to be undervalued. The current stock price of $9.29 is trading 28.3% below its estimated GF Value™ of $12.96. GuruFocus considers Prothena to be Modestly Undervalued.

Key valuation signals for PRTA:

  • Accumulated Depreciation: $-6.73 Mil
  • GF Value™: $12.96 vs. price of $9.29 (28.3% below fair value)
  • GF Score™: 74/100 with 2 warning signs

No single metric tells the full story. See the PRTA stock analysis page for a complete view including 30-year financials, guru trades, and insider activity.

Prothena Business Description

Other Exchanges 0Y3M:UK0PT:Germany
Address 77 Sir John Rogerson’s Quay, Block C, Grand Canal Docklands, Dublin 2, Dublin, IRL, D02 VK60
Prothena Corp PLC is a late-stage clinical biotechnology company that focuses on protein dysregulation and a pipeline of investigational therapeutics with the potential to change the course of devastating neurodegenerative and rare and peripheral amyloid diseases. Prothena is developing and applying its proprietary CYTOPE technology to target a broad spectrum of intracellular disease pathways in the brain and periphery. The company's pipeline includes both wholly-owned and partnered programs like Prasinezumab, Coramitug (PRX004), BMS-986446 (PRX005), PRX019, TDP-43 CYTOPE, and PRX012-TfR, being developed for the potential treatment of Parkinson's disease, ATTR amyloidosis with cardiomyopathy, Alzheimer's disease, Amyotrophic lateral sclerosis (ALS), and other neurodegenerative diseases.
74GF Score

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Accumulated Depreciation is just one metric. See GF Value™, 30-year financials, guru trades, warning signs, and more.

$9.29
Price
$12.96
GF Value